If you describe someone or something as a knockout, you think that they are extremely attractive or impressive.

knockout noun [C] (COMPETITION) (US elimination tournament) a competition in which only the winners of each stage play in the next stage, until one competitor or team is the final winner:

a panel in a casing, can, or box, esp. of metal or plastic, so designed that it can readily be removed, as by punching, hammering, or cutting, to provide an opening into the interior: a knockout in a junction box.

knock•out (ˈnɒkˌaʊt) n. 1. an act or instance of knocking out. 2. the state or fact of being knocked out. 3. a knockout blow. 4. Informal. a person or thing overwhelmingly attractive, appealing, or successful.

Definition of knockout noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

• He may not have a knockout punch, but he does have good moves all the way to the bell. • It was a knockout punch of which Indurain, Hinault or Merckx would have been proud.

KNOCKOUT definition: an act or instance of knocking out. See examples of knockout used in a sentence.

KNOCKOUT meaning: 1 : an occurrence in which a boxing match ends when a fighter has been knocked down by a punch and is unable to start fighting again before 10 seconds have passed; 2 : a …

Dec 14, 2025 · knockout (plural knockouts) The act of making one unconscious, or at least unable to come back on one's feet within a certain period of time; a TKO.

The meaning of KNOCKOUT is the act of knocking out : the condition of being knocked out. How to use knockout in a sentence.